Does Prostate Cancer-produced Testosterone (T) Show Up In Normal T, Test?

[john4803]

I have been on Lupron, Erleada & Xgeva for 3 months. T has dropped from 331 to 42, 43 & 39, respectively. First 3 taken @ 2pm & last @ 8am, in the day.

PSA has continued to drop from 7.3, 0.7, 0.3 & now 0.2, respectively. It seems that the T should be dropping more? Is it reflecting the T made by the PCa, also? If so, am I becoming resistant? Will discuss with Medical Oncologist, later today, but wanted all of the "experts" here opinions!

Thanks!

[Tall_Allen]

The adrenal glands are the second largest sources of testosterone after the testicles. Internal manufacture by the cancer itself is a minor source. As long as Erleada is effective in blocking the androgen receptor, as evidenced by your low PSA, you are ok (but see the ACIS trial below). The testosterone manufactured by your adrenals has nowhere to go and accumulates in your blood serum. There is some evidence that the combination of Zytiga (which blocks adrenal synthesis) and Erleada (which blocks the androgen receptor and prevents its upgrading) may be particularly potent:

practiceupdate.com/c/113908...

While that trial did not show statistically significant improvement in overall survival, it did not have the sample size necessary for that. It did prove that radiographic progression was significantly delayed by the combination. You may want to discuss adding Zytiga.

[john4803 in reply to Tall_Allen]

Great answer, TA! Thanks!

[john4803]

smurtaw, as a retired engineer, I really appreciate your answer! 👍👍

[john4803]

I apologize that I just saw your reply, smurtaw. I agree that we love numbers & I love spreadsheets, etc. Helps keep my mind sharper, I think? We are trained problem solvers but we can't solve PCa with a formulae, unfortunately!

As you note in your bio, about your wife, mine is a great supporter, too, especially since she is a retired Dietitian, also, & watches my food intake! Best of luck to you in this challenge & struggle.